HLE No ToolsactiveReasoning
HLE No Tools: Humanity's Last Exam — No Tools
Metric: Accuracy (higher is better)Introduced: 2025
Humanity's Last Exam expert-level cross-domain reasoning benchmark measured without external tools. Kept separate from with-tools and Pro-compute variants.
Models ranked
2
tracked on this benchmark
Score band
49.8 – 41.4
best → lowest tracked
Snapshot trend
+8.40
Apr 24 → May 28 · 1 models
Leaderboard
Tracked models ranked by Accuracy (higher is better).
#Model variant and provenanceRelative to leaderScore
1
Claude Opus 4.8
49.8Version: HLE no toolsHarness: Not recordedEvaluator: Not recordedObserved: May 28, 2026Confidence: Not recordedSource
Notes: Official Anthropic launch benchmark.
2
GPT-5.5 Pro
41.4Version: HLE no tools; standard GPT-5.5 weightsHarness: Not recordedEvaluator: Not recordedObserved: Apr 24, 2026Confidence: Not recordedSource
Notes: No-tools variant kept separate from with-tools and Pro-compute HLE rows.
How to read this benchmark
This benchmark scores models where higher is better. Use scores for directional filtering and shortlisting, not universal quality ranking; then validate pricing, context window, provider availability, and fit for your workload.
Trust this score when
- There is a fresh timestamped snapshot (or multiple snapshots) for this benchmark.
- The model list covers the same version family you can actually deploy today.
- Top candidates overlap with your required routing and feature requirements.
Be cautious when
- There is only one benchmark snapshot or the dataset appears stale.
- The benchmark metric direction is opposite of your decision objective.
- The score difference between options is narrow and likely within implementation variance.
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Last reviewed: Jun 17, 2026